1. Field of the Invention
The present invention relates to horizontal hinged doors such as cellar, bulkhead or hatchway doors and, in particular, to the use of a gas cylinder as a lifting mechanism in which the lifting force of the gas cylinder is easily adjustable by the user of the door using a specially designed bracket which rotatably couples the gas cylinder to the door leaf and to the use of braces to control the concentrated force exerted by the gas spring which force is potentially damaging to the door assembly. Components of the door assembly are also preferably provided with studs to facilitate handling and shipping and on-site construction by the installer.
2. Description of Related Art
There are numerous applications in which the hinge line for a door or other object is non-vertical. Such applications include, among others, hatch covers for roof openings, flush-mounted sidewalk doors, and, as illustrated here, the entrance doors for exterior basement entrances. Because the hinge line is at least partially horizontal in such applications, the weight of the door must be supported until the center of mass of the door is raised over the hinge line.
Doors of the type described are often quite heavy and can be dangerous due to the tendency to close rapidly and with great force when released. Accordingly, it has long been the practice to counterbalance the door, not only for increased safety, but also to permit the door to be opened and closed more easily with less force. For convenience, the following description will be directed to cellar doors although it will be appreciated by those skilled in the art that the invention can be used on other horizontal doors.
As discussed in U.S. Pat. No. 4,873,791, assigned to the assignee of the subject patent application, typically, the required counterbalancing torque is derived from torque rods, springs, or gas cylinders. Torque rods are noted to have a particular advantage that they provide the counterbalancing torque as a result of the rotation of one end of the rod relative to the other and the appropriate selection of the torque rod dimensions have provided a simple means for partial counterbalancing of the door. Torque rods are also noted to have the advantages that their long thin shape can be positioned out of the way behind the doorframe and they are extremely rugged and reliable.
While the use of the torque rods are very advantageous and used throughout industry for this type of door, there is a need to provide a door that would be beneficial to both the user such as a homeowner and to the installer for simplifying the installation process. The new door would be easier to use and adaptable to different lifting forces and will have increased resistance to vibration and rattling due to the effect of high winds.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide a horizontal hinged door assembly and, in particular, a cellar door assembly using a gas spring to assist opening and closing the door wherein the lift forces needed to lift the door can be easily adjusted without tools or training.
It is another object of the present invention to provide horizontal hinged doors which are constructed with sidewalls and horizontal hinged doors that use existing foundation sidewalls which doors are fabricated using a gas spring as a lifting device.
A further object of the present invention is to provide a horizontal hinged door which decelerates the movement of the door leaf during opening of the door and firmly supports the door without the need of an additional hold-open device and allows the user to close the door leaf with one hand rather than two.
It is yet another object of the present invention to provide a horizontal hinged door comprising a number of sections which are assembled on the job site to form the door, which sections have assembly studs welded in the factory so that damage to the door during shipping is minimized and the door may be packaged in a smaller container for the cost effectiveness and convenience of shipping and handling.
Still other objects and advantages of the present invention will in part be obvious and will in part be apparent from the specification.
The above and other objects and advantages, which will be apparent to those skilled in art, are achieved in the present invention which is directed to, in a first aspect, a horizontal door comprising:
a frame surrounding an opening, the frame having a flat surface and angular vertical sidewalls, the angular sidewalls preferably having inwardly turned foundation flanges at the base of the sidewall;
one or more door leafs hinged to the frame for movement between an elevated open position and a closed position;
a bracket mounted on the frame having one or more spaced through openings therein to accommodate a pivot pin;
an elongated brace extending from the bracket to the foundation flange; and
a pressure device having a rod rotatably coupled to a through opening in the bracket and a cylinder rotatably coupled to the door, the pressure device resiliently urging the door leaf to its open position.
In a further aspect of the invention, a horizontal door is provided comprising:
a frame surrounding the opening, the frame having a flat surface and a downwardly extending flange plate running along the frame and having one or more through openings in the plate;
one or more door leafs hinged to the frame for movement between an elevated open position and a closed position;
a bracket mounted on the frame having one or more spaced through openings therein for accommodating a pivot pin and one or more communicating through openings that extend through the bracket and through the flange plate;
a fastener passing through the through opening in the bracket and the flange plate and engaging the side of the opening; and
a pressure device having a rod rotatably coupled to a through opening in the bracket and a cylinder rotatably coupled to the door, the pressure device resiliently urging the door to its open position.
In another aspect of the invention, various door assembly sections assembled on-site to make the horizontal door are provided with studs, preferably threaded, which studs are used by the installer to simply and easily fabricate the horizontal door and which studs enable packing the door assembly sections in a smaller package for cost effectiveness and convenience of shipping and handling.